#include <stdio.h>

void Quicksort(int data[], int left, int right){
    int l = left, r = right;
    int pivot = data[(left + right) / 2];
    int temp;

    while(1){
        while (data[l] < pivot) l++;
        while (pivot < data[r]) r--;
        if(r < l) break;

        temp = data[l];
        data[l] = data[r];
        data[r] = temp;

        l++, r--;
    }
    if(left < r)  Quicksort(data, left, r);
    if(l < right) Quicksort(data, l, right);
}

int main(void){
    int i, N, same = 0, ans = 1000000;
    scanf("%d", &N);
    if(N-1){
        int x[N+1];
        for(i=1;i<=N;i++){
            scanf("%d", &x[i]);
        }
        Quicksort(x, 1, N);
        for(i=1;i<N;i++){
            if(x[i]==x[i+1]){
                same++;
            }else if(x[i+1]-x[i]<ans){
                ans = x[i+1]-x[i];
            }
        }
        if(same==N-1){
            printf("0\n");
        }else{
            printf("%d\n", ans);
        }
    }else{
        scanf("%d", &N);
        printf("0\n");
    }
    return 0;
}